Arrangement for adjustment of the position of the supporting posts for a cylindrical body upon which a layer of weld metal is being deposited

ABSTRACT

An arrangement for adjustment of the position of supporting posts of a cylindrical body in order to compensate for thermal expansion in its longitudinal direction. In the course of depositing a metallic layer on the circumference of the body by welding on, a minimum clearance is maintained between the faces of the cylindrical body and both supporting posts, so as to maintain the position of the longitudinal center of the cylindrical body in the center of the distance between the supporting posts.

United States Patent Majek et al. Mar. 7, 1972 [54] ARRANGEMENT FOR ADJUSTMENT References gggggffgggg gggga UNITED STATES PATENTS 2,648,040 8/1953 Schneider ..3l8/286 YLINDRICAL BODY UPON WHICH A 3,398,254 8/l968 Rietsch ..219/97 LAYER OF WELD METAL IS BEING DEPOSITED Inventors: Vladlmir Maiek; Anton Kraimer; Zdenek Primary Examiner-Bemard A. Gilheany Assistant Examiner-W. E. Duncanson, Jr. Attorney-Arthur O. Klein 5 7] ABSTRACT An arrangement for adjustment of the position of supporting posts of a cylindrical body in order to compensate for thermal expansion in its longitudinal direction. In the course of depositing a metallic layer on the circumference of the body by welding on, a minimum clearance is maintained between the faces of the cylindrical body and both supporting posts, so as to maintain the position of the longitudinal center of the cylindrical body in the center of the distance between the supporting posts.

4 Claims, 3 Drawing Figures Patented March 7, 1972 2 Sheets-Sheet 1 m muwu W AJW Q Y m m m EMM W vwa m Ndmm T A dnz Patgnted March 7, 1912 3,648,140

2 Sheets-Sheet 2 a H gnton KRAJMER Jgne/(SMITMAJER By: yam aw ATTORN EY ARRANGEMENT FOR ADJUSTMENT OF THE POSITION OF THE SUPPORTING POSTS FOR A CYLINDRICAL BODY UPON WHICH A LAYER OF WELD METAL IS BEING DEPOSITED BACKGROUND OF THE INVENTION when depositing a metallic layer on the circumference of a roll or the like with its longitudinal axis in a horizontal plane, the rollis generally supported by its necks on supporting posts which exactly determine the position of the body being operated upon with respect to the welding-on'apparatus.The

exactlongitudinal position of the body is secured by tight clamping of the body,.in the direction of its longitudinal axis, between the supporting posts. Because of such tight clamping of the body between the supporting posts, the problem of eliminating high stresses and pressures arises; these high stresses and pressures are generated between the contactfacesof the supporting posts andof the clamped roll due to thermal expansion of the body caused by heat generated in thecourse of the welding-on process and/or by prior heating of the body.

Mechanisms which have been used to solve this problem have at least one of the supporting posts mobile and adjustable with respect to the other post, in order to enable the same supporting posts to be used for bodies of different lengths. The body is adjusted after it has been seated on the supporting posts so as to have a minimum clearance between it and the posts in the direction of the-longitudinal axis of the body. The mobile supporting post is thereafter fixed, and the position of the body being treated is fixed with respect to the welding-on apparatus. The minimum clearance is determined by the required accuracy which the processed body has to maintain with respect to the welding-on apparatus. A drawback of this method of fixing of the cylinder is the fact that the change of the length of the body due to thermal expansion generally exceeds this minimum clearance, and the supporting posts are thus exposed to high stresses and can eventually suffer damages.

Another method of adjustment of the supporting posts takes thermal expansion of the'body into account, and the posts are adjusted so that an expansion of the body is possible-without any undue stresses. A drawback of thismethod is the inaccuracy of the longitudinal position of the body being treated with respect to the welding-on apparatus, so that the position of the body can spontaneously change in direction of its longitudinal axis from engagement withone supporting post to engagement with the other. This axial movement of the body is undesirable for most cases of welding-on, and is highly undesirable or not to be tolerated in the welding-on of grooved rolls.

Another known mechanism employed to solve the problem uses supporting posts shifted by adjusting screws driven 'by electric motors which are controlled by the operator inthe course of welding. A drawback of this mechanism is that it requires an increased attention of the operator, although there is no guarantee that the attendant will adjust the supporting posts through the correct distance so that there is both a minimum clearance between the mountings for the body so as to prevent any undesired shifting of the body in the direction of its longitudinal axis but one which prevents any dangerous stresses between the contact faces of the supporting posts and the body being treated.

SUMMARY OF THE INVENTION It is an object of this invention to provide an arrangement for the adjustment of the position of the supporting posts for a generally. cylindrical body in the course of depositing a metallic layer on its surface by welding, where a minimum clearance between the supporting posts and the body in the direction of the longitudinal axis of the body is automatically maintained and excessive stresses in this direction are eliminated.

It is another object of this invention to provide an apparatus which maintains a once-established position of the processed body-in the direction of its longitudinal axis with respect to the welding apparatusbeing-used, while eliminating excessive stresses between the processed body and its supporting post's.

Bearing these and other objects in mind, we provide pickup devices on both the supportingposts of the processed cylindrical body, the.feelers of which pickup devices contact faces taking part in the thermal expansion of the cylindrical body, whereby. a series connection of working contacts of both pickup devices is connected in parallel with the recording part of the control circuit of a control element controlling the mutual withdrawal of both supporting posts, the logic multiple of signals from said pickup devices being brought to the recording input of a storagecircuit which controls said control element.

DESCRIPTION OF THE DRAWINGS DESCRIPTION OF A PREFERRED EMBODIMENT The illustrative arrangement comprises two supporting posts 1 and 2, which are adjustable along guiding 3 and 4 on the machine frame 5. The body 6, which is shown as the grooved roll of a rolling mill, on which a metallic layer is to be deposited, must -be mounted, in order to secure its correct position in the course of the welding-on operation. The outer end faces 7, 8 of split sleeves 9, 10 which are secured to both necks of the body 6 itself, touch the faces l3, 14 of supporting rollers 15', 16 provided on the supporting posts 1, 2. In order that this condition shall be maintained, both supporting posts 1, 2 are linked by an adjusting screw 17 with rightand lefthand threads of the same pitch on its opposite ends, so that for one direction of turning of screw 17, supporting posts 1, 2 approach each otherand, for the other direction of turning of screw 17, they are moved away one from the other.

The adjusting screw 17 is mounted on the machine frame 5 in a bearing 18 so as to prevent any movement in its longitudinal direction coincident with the direction of the longitudinal axis of the body 6. Thus, the once-adjusted position of the center between both supporting posts 1, 2 remains constant with respect to the machine frame 5. Power transmission means 19, 20, for example, lever transmissions of known design, are provided on the supporting posts, transmitting the position of the respective feeler or pickup devices [(11 and K12. The transmission means 19, 20 are adjusted so that the changeover of the contacts of the pickups K11, K12 from their normally closed position to their open position is brought about when the faces 7, 8 of the sleeves 9, 10 or the faces 11,

12 of the cylinder 6 come in touch with the faces 13, 14 of the supporting rollers l5, 16. The return changeover of the pickups K11, K12, that is, the changeover from the open to the closed position is brought about when the faces 7, 13 or the faces 8, 14 are withdrawn from the pickups for the distance X which represents the minimum clearance of the cylinder 6 in the supporting posts I, 2. The adjusting screw 17 is driven by way of a coupling 21 and a gear 22 by a reversible motor 23, for instance, by an electric motor, a rotary hydraulic motor, or the like.

The reversing of such motor is accomplished by contactors having coils S1, S2-or by other suitable elements controlled automatically as indicated in FIG. 3. The wiring circuit there shown is a novel electrical storage circuit of which the control coils S1, S2 are parts; in such circuit the order for one direction of rotation of the motor 23 is accomplished by closing working contacts 1A1 by a first directional pushbutton, and the order for the other direction of rotation by the closing of working contacts 1A2 by a second directional pushbutton. The motor 23 is stopped by opening rest contacts 2A3 by operation of a stop button.

The coils S1, S2 of the forward and reverse contactors are mutually interlocked by rest contacts 281, 282 of the contactors and by the rest contacts 2A1, 2A2 of the directional pushbuttons. In addition, the coils S1, S2 of the forward and reverse contactors can be protected by end stops 2K1, 2K2 which generally determine the total range of longitudinal adjustment of posts 1 and 2 which is possible. The holding contacts 181, 182 of the contactor coils S1, S2 represent the socalled sequential logical function.

The individual parts of the wiring diagram of FIG. 3 have the following functions: the part between points 100-101 is a common blanking circuit for the coils S1, S2 of the forward and reverse contactors. The part between points 101-102 is a holding circuit for the coil S1 of the respective contactor. The part between the points 101-103 is a holding circuit for the coil S2 of the other respective contactor. The part between points 102-104 is a blanking or circuit opening part for the contactor coil S1. The part between the points 103-105 is a blanking or circuit opening part for the contactor coil S2.

The recording input of the logic storage circuit with or without contacts is that part of the circuit causing a change of the circuit from the zero, or open, inoperative position to the unit, or closed, operative position, if a signal, for instance, an electric signal, is applied to said input, the circuit remains thereafter in that condition, for example, in the unit position even after this signal has ceased. If signals are simultaneously applied to both the circuit holding and circuit opening inputs, the circuit remains always in its zero position. The unit position of the circuit is, for instance, characterized by energizing a relay, a contactor, or by generating a voltage at its output.

The zero" position of the circuit is, for instance, characterized by the deenergizing of a relay, of a contactor, by disconnecting of contacts or by disappearance of the voltage at its output. 7

The circuit of FIG. 3 according to this invention includes the following additional elements: The branch circuit of the coil S1 of the respective contactor, that is, of the contactor for the supporting posts 1, 2 to approach each other is completed by a series connection of a circuit composed of a parallel connection of rest contacts 2K11, 2K12 of the position pickups K11, K12; the rest contacts are closed when the feelers of the pickups do not engage the shoulders on the body being treated. Thus, an approach of the supporting posts 1, 2 toward each other is possible only if at least one of the position pickups K11, K12 does not rest with its feeler against the respective shoulder of the body 6. A branch circuit composed of a series connection of working contacts 1Kl1, 1K12 of the position pickups K11, K12 is connected in parallel to the holding circuit of the circuit of the coil S2 of the contactor which causes the withdrawal of the supporting posts 1, 2 from each other. Contacts [K11 and 1K12 are normally open and are closed only if the feeler of the respective pickup contacts the respective end of the body 6. Thus, an automatic withdrawing of the supporting posts 1, 2 is effected if both position pickups K11, K12 simultaneously contact the respective faces of the body 6. As a result, if due to the thermal expansion of the body 6 its front faces 11, 12 or 7, 8 are in contact with the faces 13, 14 of the supporting rollers 15, 16, the apparatus operates to carry out its automatic adjustment to obtain the desired clearance X.

Interposed between the contacts 182 and the junction 103 are normally closed contacts 1B1 of an auxiliary relay B1 the coil of which is connected in series with contacts 131. Relay B1 is provided with a second set of contacts designated 381, contacts 331 being normally open.

During the action of the holding circuit for the working contacts 1K11, 1K12, relay B1 and its contacts 131 and 3B1 prevent the action of the holding contact 182 of the coil S2. As we have seen, coil S2 controls the withdrawal of the supporting posts 1, 2. Contact 181 of the auxiliary relay B1, which is energized only if the contact 1A2 of the pushbutton for the opposite direction is closed, is introduced in series with the holding circuit of the branch circuit of the contactor coil S2. The relay B1 causes the retaining contact 182 to close only if an order is given by the operator. The normally open contacts 381 of the relay Bl prevent the energizing of the relay Bl by the potential of junction 103.

The apparatus of the invention operates as follows: The body 6 to be treated is seated on the drawn-away supporting posts 1, 2. The position pickups K11, K12 are in their zerd position. By pressing the working contact [A1 of the first directional pushbutton the contactor coil S1 is energized, remains energized by the closed retaining contact 181, and gives an order for the approach of the supporting posts 1, 2 toward each other. The supports continue to approach each other until contact of the faces 13, 14 of the supporting rollers 15, 16 is established with the faces 7, 8 of the sleeves 9, 10. The contacts 2K11, 2K12 are accordingly interrupted, the

contactor coil S1 is deenergized, and the approach of supports 1 and 2 toward each other is stopped. Simultaneously, the circuit of the working contacts 1K11, 1K12 is closed, the contactor coil S2 is energized, the movement in the opposite direction starts, the supporting posts 1, 2 start to be withdrawn. This withdrawal continues until at least one of the position pickup K11, K12 is changed into its zero" position, that is, until at the left or right supporting post a clearance X is formed. The contactor coil S2 is thereafter deenergized and the separating movement of supports 1, 2 ceases.

If now, due to thermal expansion, both position pickups K11, K12 are again brought into their unit position, the contactor coil S2 is energized, the separation of both supporting posts 1, 2 starts again and continues until there is formed a clearance X on one or the other end of the body 6.

As the travel required for changeover of the position pickups of known design does not need to be larger than 0.1 mm., the arrangement is capable of maintaining the body 6 in a chosen position, within very close limits, with respect to the center of both supporting posts 1 and 2.

Although the invention is illustrated and described with reference to one preferred embodiment thereof, it is to be expressly understood that it is in no way limited to the disclosure of such a preferred embodiment, but is capable of numerous modifications within the scope of the appended claims.

What is claimed is:

1. An apparatus for the automatic compensation of thermal expansion of a body in the course of depositing a metallic layer thereon by welding metal on the circumference of the body, comprising in combination: a machine frame, two posts for supporting the body with its longitudinal axis horizontal, means mounting both said supporting posts slidingly on the machine frame, driving means for simultaneously causing said supporting posts selectively to approach and to be withdrawn from each other, pickup devices having feelers provided on each of said supporting posts contacting with their feelers faces of the body which move longitudinally upon the longitudinal thennal expansion of the body, said pickup devices provided with changeover switches operating in response to changes in the position of the extremities of the cylindrical body with respect to the supporting posts, control elements for controlling the driving means for the selective mutual approach toward and withdrawal of the supporting posts from each other, a control circuit for the control of said control elements, said control circuit comprising a branch for each of both control elements for the approach and the withdrawal of both supporting posts respectively, said branches being connected in parallel, a common blanking circuit connected in series with the parallel connected branch circuits, each of said branch circuits comprising a holding part and a blanking part connected in series, the changeover switches of both pickup devices having working contacts in series connection connected in parallel to the holding part of the branch for withdrawal of both supporting posts.

2. An arrangement as claimed in claim 1, comprising an auxiliary relay connected to be deenergized in the course of withdrawal of both supporting posts, said relay having a contact connected in series with a self-holding contact of the control element for withdrawal of both supporting posts, said control element being part of the recording part of the control circuit for withdrawal of both posts.

3. An arrangement as claimed in claim 1, wherein the changeover switch of each pickup device has a rest contact, said rest contacts being in a parallel connection which is connected in series with the branch for causing the approach of both supporting posts, and means for impressing the logic sum of negations of said impulses upon the blanking part of said branch.

4. An arrangement as claimed in claim 1, comprising an adjusting screw with portions with leftand right-hand threads driven by said driving means, said portions of the screw being in engagement with the respective supporting posts, and means joumaling the screw and preventing an axial movement of said screw. 

1. An apparatus for the automatic compensation of thermal expansion of a body in the course of depositing a metallic layer thereon by welding metal on the circumference of the body, comprising in combination: a machine frame, two posts for supporting the body with its longitudinal axis horizontal, means mounting both said supporting posts slidingly on the machine frame, driving means for simultaneously causing said supporting posts selectively to approach and to be withdrawn from each other, pickup devices having feelers provided on each of said supporting posts contacting with their feelers faces of the body which move longitudinally upon the longitudinal thermal expansion of the body, said pickup devices provided with changeover switches operating in response to changes in the position of the extremities of the cylindrical body with respect to the supporting posts, control elements for controlling the driving means for the selective mutual approach toward and withdrawal of the supporting posts from each other, a control circuit for the control of said control elements, said control circuit comprising a branch for each of both control elements for the approach and the withdrawal of both supporting posts respectively, said branches being connected in parallel, a common blanking circuit connected in series with the parallel connected branch circuits, each of said branch circuits comprising a holding part and a blanking part connected in series, the changeover switches of both pickup devices having working contacts in series connection connected in parallel to the holding part of the branch for withdrawal of both supporting posts.
 2. An arrangement as claimed in claim 1, comprising an auxiliary relay connected to be deenergized in the course of withdrawal of both supporting posts, said relay having a contact connected in series with a self-holding contact of the control element for withdrawal of both supporting posts, said control element being part of the recording part of the control circuit for withdrawal of both posts.
 3. An arrangement as claimed in claim 1, wherein the changeover switch of each pickup device has a rest contact, said rest contacts being in a parallel connection which is connected in series with the branch for causing the approach of both supporting posts, and means for impressing the logic sum of negations of said impulses upon the blanking part of said branch.
 4. An arrangement as claimed in claim 1, comprising an adjusting screw with portions with left- and right-hand threads driven by said driving means, said portions of the screw being in engagement with the respective supporting posts, and means journaling the screw and preventing an axial movement of said screw. 